They studied three types of coffee (light roast, dark roast and decaffeinated dark roast) and conducted experimental tests that showed the effects of a group of compounds known as phenylindanes, which form during the process of roasting coffee beans and give coffee its bitter flavor.
According to the study, the compounds inhibited two protein fragments often found in Alzheimer’s and Parkinson’s patients from “clumping.”
"So phenylindanes are a dual-inhibitor," lead researcher Donald Weaver said in a statement. It's "very interesting, we were not expecting that."
Because roasting leads to higher quantities of phenylindanes, dark roasted coffee seems to be more protective than light roasted coffee, according to Weaver and his colleagues.
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“It's the first time anybody's investigated how phenylindanes interact with the proteins that are responsible for Alzheimer's and Parkinson's,” fellow researcher Ross Mancini added.
While it’s unclear how beneficial those compounds are and more research is needed to understand how such findings can “translate into potential therapeutic options,” the research demonstrates “that there are indeed components within coffee that are beneficial to warding off cognitive decline,” Weaver said. “It's interesting but are we suggesting that coffee is a cure? Absolutely not.”
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Alzheimer's disease is the sixth leading cause of death in the United States. In fact, the death rate from the disease has risen by 55 percent in recent decades, according to the CDC. And in Georgia, the number of deaths from Alzheimer's has increased by 201 percent since 2000, according to Georgia Health News.
The Atlanta-based Centers for Disease Control and Prevention recently revealed that the country’s burden of Alzheimer’s disease and related dementias will double by the year 2060.
In 2014, 5 million Americans — or 1.6 percent of the population — felt the burden of the diseases. The figure is expected to grow to 13.9 million, equating to nearly 3.3 percent of the projected population in 2060.
According to the Parkinson's Association, an estimated seven to 10 million people in the world are living with the neurological disease.
Read the full study at frontiersin.org.